The present invention relates to a method allocating/sharing resources among users of a communication network. The field to which the invention applies comprises all point-to-multipoint communication networks in which resources are shared. The resources to be allocated are principally transmission resources, for example channels defined by times, frequencies and/or physical communication nodes. Similarly, the invention can be transposed to the field of multitasking applications or multi-processor and multitasking applications. In the context of a multitasking environment, a processor is a central point at which the various processes are executed. In this case the resource is a processing resource. The object of the invention is to guarantee users optimum access to a resource without wasting the resource and to assure the various users the minimum quantity of resource to be provided under their contract. Another object of the invention is to provide a high-performance transmission service without having to overrate the transmission equipment.
In the prior art users can already enter into a contract to use a telecommunication network. There are two kinds of contract. A first kind guarantees a particular quantity of resource to users when they have logged onto the network, for example a particular bandwidth. When a user logs on, the network knows the maximum bandwidth and the number of users who have already logged on. The network determines whether the new user can log onto the network without exceeding the bandwidth. If so, the new user is permitted to log on with a given bandwidth. If not, the request to log on is refused and the user has no access to the network. In this case a user attempting to log on is allocated some of the bandwidth, i.e. some of the resource, until they log off. The resource allocated to the user during this period cannot be used by anyone else, even if the user is not actually using the resource himself while he is logged on. This situation is problematical because, although transmission resource is available, in the sense that it is not being used, there may be users who cannot log on.
The second prior art solution allows all users who request to log on to do so. The resource is then shared equally between all users who are logged on at the same time. If a large number of users log on, the resource collapses. Each user is allocated an equal fraction of the resource. As and when new users log,on, that fraction is reduced in size. The problem of the first situation is encountered again here. All users who have logged on are allocated a portion of the resource, which they do not necessarily make use of. Users who are making use of the resource have very little resource available to them. In the case of transferring data, the transmission bit rates are low. Taking the example of a resource consisting of a transmission channel with a total bit rate of 10 kbit/s, if 100 users are logged on, each is allocated a bit rate of 100 bit/s. The situation can arise in which 99 of the 100 users who have logged on have nothing to transmit but one user has 100 kbits to transmit. Transmission will then occur at 100 bit/s, even though there is nothing in transit on the remainder of the channel.